1. Field of the Invention
This invention relates generally to ignition devices, and, and more particularly to a swirl chamber and spark plug assembly which carries a spark plug having an extended firing end and has apertures at the lower end which impart swirling action to the fuel-air mixture and generates torch jets for rapid and uniform energy conversion in the engine combustion chamber.
2. Brief Description of the Prior Art
There are several patents which disclose various auxiliary combustion chambers and modified spark plug devices provided by others in attempts to overcome the deficiencies of the conventional spark plug arrangement in internal combustion engines.
The U.S. Patents to Browning (2,100,320), Pielstick (2,677,356), Goto (4,071,001), and Noguchi et al (4,127,095), disclose precombustion chamber devices wherein the lower portion of the chamber below the firing end of the spark plug is partitioned into parallel spaces or provided with a center core or divider having vertical and radial walls which act as fuel passage channels. These types of precombustion chambers do not utilize a centrifugal or helical swirling action for the fuel-air mixture.
The U.S. Patents to Benedikt et al (4,416,228), Bamer et al (4,465,031), and Breuser et al (4,509,476) disclose precombustion chamber devices which impart a whirling or twisting action to the fuel-air mixture, but the wall of the combustion chamber cooperates with the spark plug electrode to form the spark gap. These devices do not suggest the use of a spark plug having an elongated firing end wherein the electrode gap is extended into the area just above the lower chamber.
Flores, U.S. Pat. No. 4,499,399 discloses a spark plug adapter wherein an upper chamber encompasses the spark plug electrodes and communicates with a lower chamber through an acceleration orifice and a transverse deflector imparts turbulence to the combustion products. Flores does not utilize a centrifugal or helical swirling action for the fuel-air mixture, nor a spark plug having an elongated firing end.
Blais, U.S. Pat. No. 4,542,724 discloses a flame injector sleeve that receives a conventional spark plug within a chamber having a forward end which has a frusto-conical interior surface with a bottom aperture and five holes through the side wall which are tapered upwardly at a clockwise angle and inwardly at thirty degrees relative to the side wall. Blais does not suggest the use of a spark plug having an elongated firing end wherein the electrode gap is extended into the area just above the holes.
The present invention is distinguished over the prior art in general, and these patents in particular by a swirl chamber and spark plug assembly comprising a unitary cup-shaped swirl chamber member having external threads for removably installing it in the spark plug receiving hole of an internal combustion engine and a reduced diameter lower portion at the opposite end. The interior of the swirl chamber has a central bore with internal threads at the top end and a stepped cylindrical swirl chamber defined by a lower cylindrical chamber and an upper cylindrical chamber of larger diameter for swirling gas in relation thereto. A spark plug having elongated electrodes is threadedly received in the top end of the swirl chamber with the spark plug gap at the juncture between the upper and lower chambers. A series of circumferentially spaced small diameter orifices at the bottom of the lower chamber extend angularly inward and upward through the side wall of the swirl chamber body tangent to the side wall of the lower chamber and a small diameter central orifice extends axially through the bottom wall for drawing a fuel-air mixture into the stepped swirl chamber and injecting flames from the swirl chamber interior into the engine combustion chamber. When received in the spark plug hole of the engine, the reduced diameter portion of the swirl chamber protrudes slightly into the engine combustion chamber to expose the orifices for maximum fuel-air mixture and flame communication with the engine combustion chamber.